Selectively operable mechanically and fluid actuated lifting truck



June 3 F. .1. SHEPARD, JR., ET AL 72,161,659

SELECTIVELY OPERABLE MECHANICALLY AND FLUID ACTUATED LIFTING TRUCK Filed Oct. 24, 1956 5 Sheets-Sheet l v ln'venTors. Fred ericK U. Sh epard Ur.

NaThaniel War. sh aw byM June 1 F. J. SHEPARD, JR., ET AL 2,161,659

SELECTIYELY .OPERABLE MECHANICALLY' AND FLUID ACTUATED LIFTING TRUCK Filed Oct. 24. 1936 s Sheets-Sheet 2 w, ft m M ed. 4 QM e hf v e 6 k m2 m&m 86a QW S. 1 .2 m.m N. am L h. mm WN m- June 6, 1939.- F. J. SHEPARD, JR., ET AL 2,161,659

'SELECTIVELY OPERABLE MECHANICALLY.AND FLUI D ACTUATED LIFTING TRUCK I Filed Oct. 24, 1936- 5 Sheets-Sheet s ln venTor s.

Frederick U. Shepard Urr Ncflhoniel Wurshdw b wwm I June 6, 1939. F. J. SHEPARD, JR., ET AL 2,161,659

SELECTIVELY OPERABLE MECHANICALLY AND FLUID ACTUATED LIFTING TRUCK Fil ed Oct. 24, 1,936 5 Sheets-Sheet 4 m m A 3 5 m w .7 li m n ATTys.

June

F J. SHEPARD, JR, ET Al.

Filed' Oct. 24, 1936 SELECTIVELY OPERABLE MECHANICALLY AND FLUID ACTUATED LIFTING TRUCK 5 Sheets-Shee t 5 mm, :17/ fi 'F'redeYcK U, Shepard Ur.

Nuthcmie! Worshaw WWAUZMM Patented June 6, 1939 UNITED STAT S snmc'rrvnrx oramm: rmcnamcaum AND rum) ao'rns'rizn mr'rnvc TRUCK Frederick J. Shepard, In, West Newton, and Nathaniel Warshaw, Belmont, Masa, assignors to Lewis-Shepard Company, Watertown. lilasa, a

corporation of Massachusetts V Application October 24, 1936, Serial no. 107,422

reclaim 1(01. ass-1o) invention relates to improvementsin ele vating trucks having an upwardly movable platform adapted to be introduced beneath the article to be transported, or more usually beneath a skid supporting one or more articles to be transported, with means for raising the load supporting means to lift the article or skid from the floor a sufficient distance to enable it to be transported by the truck to its destination.

:Elevating trucks of this character are employed to transport not only relatlvelylight loadsgbut very heavy loads, and it is desirable in order to save time and effort-upon the part of the operator t'o providemanually operable means for raising the weighted load supporting means to the desired height rapidly when a light load is being transported, or to employ such manually operable force multiplying means aslto, enable heavy loads to be lifted with a minimum effort uponthepart of the operator.

- Inasmuch as it is desirable to have the load supporting means when in lowered position a, considerable distance below the article or skid so I that the truckcan be conveniently manipulated in backing the same beneath the article or skid, it is desirable that means shall be provided for rapidly raising the load supporting means until the under surface of the article or skid is engaged by the load supporting means, and if the load is not a heavy one for further raising the load supporting means to the desired height for transportation of the article. However, where 'heavy loads are to be transported it is desirableto em ploy force multiplying means for raising the .35 load supporting means afterit has engaged the under surface of the article or skid. We are aware that this has heretofore been accomplished by providing fluid actuated lifting; mechanism comprising a lifting cylinder and ram for rais- 4 ing the load supporting means with a plurality of pumps selectively operable to force fluid under pressure into the ram cylinder as disclosed in the patent to Daniel E. Hennassy No. 2,009,970

granted July 30, 1935, but in this construction 4-3 the manipulation of the pump plunger. for raising 1 the load supporting means rapidly requires a plurality of reciprocations and also requires manipulation of mechanism to disconnect the actuating mechanism from the pump plunger which is not i to be employed in the lifting operation.

- means is greatly multiplied over that exerted by anism operable thereafter to raise the load supporting means preferably step by step in which the lifting force applied to the load supporting the operator.

- The mechanicallyactuated lifting mechanism desirably is so constructed as to be operated by a foot pedal which permits the operator easily to raise the load supporting means into engagement with the under face of the article or skid 1 to be lifted, but whichalso will enable him by projecting his force suddenly upon the pedal to raise a load of substantial weight to the desired --height as is disclosed in the patents to Daniel E. Hennessy Nos. 1,867,825 and 1,887,826 granted July 19, 1932. 1' The present invention embodies the. advantageousieatures of ad of the'a bove patents and particularly comprises mechanically actuated rapid lifting mechanism for initially raising the 90 load supporting means and fluid actuated mechanism for' applying greater force to raise the weighted load supporting means rapidly step by step, Preferably the mechanically actuated load supporting means is raised by pedalmechanism 2 and the fluid actuated load supporting means operated byvertical swinging-movements of the tongue when in any steering position, as will hereinafter be described. In the preferred construction suitable means are provided for connecting the load supporting means to the fluid actuated ram, and themechanically actuated means also acts upon the iram to raise the load supporting means without is to provide means for admitting fluid into the ram cylinder to fill the space beneath the ram piston as the ram is raised and to retain it therein, so that when the mechanical lifting mechanism is released the load supporting means will be sustained at the height to which it is raised 6 and operation of the fluid actuated mechanism will thereupon raise the load supporting means step by step to the desired height.

, A further object of the invention is to provide extensible means connecting the. mechanically actuated pedal mechanism to the ram which will permit'release of the pedal mechanism when the load supporting means is raised to a predeterrri ined he ght without interfering with the further upward movement of the load supporting means 6;

, valve.

produced by operation of the fluid actuated lifting mechanism.

Another object of the invention is to provide a fluid operated jack for lifting the load supporting means having an actuating lever for reciprocating the pump plunger, with means for adjusting the effective leverage of said actuating lever to vary the force applied to the plunger and the length of the stroke of the plunger. By such adjustment of the enective leverage applied through the pump plunger actuating lever, lighter loads may be lifted by the fluid actuated lifting mechanism more rapidly by fewer strokes of the pump plunger, while exceedingly heavy loads may be lifted more slowly by a greater number of strokes of the plunger and by the application of greater force to the pump plunger.

Another object of the invention is to provide fluid actuated liftingmechanism of the character described with novel means for releasing the fluid which supports the ram and load supporting means which. comprises an outlet passage connecting the cylinder chamber to the reservoir provided with a valve having a screw threaded stem operable when rotated in one direction to close the conduit, with resilient means acting upon the valve stem' to hold the 'valve in closed position, and manually operable means for'rotating the valve in the opposite direction against the force of the spring gradually to open the By reason of this construction the descent of the load supporting means is always under manual control and the danger of dropping of the load too rapidly is obviated.

A further object of the invention is to provide an elevating truck of such construction as to provide ample clearance beneath the frame of the truck to enable it to pass over doorway sills and the abrupt angles of inclines Joining a ramp to a floor, also to enable the load supporting means to be sufficiently lowered to enable the truck tov be readily backed beneath the skid, with ample clearance and to have means for lifting the load supporting means to such height as will prevent the legs of'the article being lifted or the skid from engaging such usual obstructions as may be present in the path of the loaded truck. This is accomplished in-the present invention by providing the rear'end of the main frame with down- 55 faceof the main frame and the upper surface of the load supporting means will be in substantially the same plane when the load supporting means is in lowered position.

Another object of the invention is to provide means for holding the steering tongue normally in vertical position particularly when the load supporting means is raised by independently actuated pedal operated mechanical lifting means and for providing spring actuated means for holding the foot lever or pedal normally in substantially vertical position to permit the truck to be manipulated in a minimumspace.

Another object of the invention is to provide an elevating truck having steering mechanism including a tongue mounted to swing vertically, upwardly movable load supporting means, and means for lifting the load supporting means operable I by vertical swinging movements of the tongue with an adjustable tongue extension having means for positively locking said extens o .in longitudinally adjusted positions, thereby enabling a greater or less leverage to be applied to the lifting mechanism in correlation to the weight of the load to be lifted.

These and other objects and features of the invention will more fully appear from the following description and the accompanying drawings and will be particularly pointed out in the I across the same being shown in section and i1- lustrating the load supporting means in raised position and also showing in dotted lines the position of the load supporting means when in lowered position;

Fig. 2 is a detail view partly in section of the portion of the tubular tongue and an extension therefor and illustrating means for locking the extension in adjusted positions;

Fig. 3 is a horizontal sectional view on line 3- -3, Fig. 1, viewed downwardly, and illustrating particularly the main frame of the truck and the manner in which the load supporting means is mounted thereupon;

Fig. 4 is a front elevation of the truck illustrated in Fig. L'the front portion or head of the frame being broken away and the positions of the steering wheels and rear wheels illustrated in dotted lines;

Fig. 5 is a detail view, mainly in vertical section on line 5-!) Fig. 6, of the fluid operated power unit showing the manner in which it is mounted upon a horizontal shaft in the main frame which is shown in elevation, and also showing the ram and ram shaft in elevation, and the manner in which the ram is pivotally mounted upon a shaft whichis connected to the load supporting means;

Fig. 6 is a horizontal sectional view on line 6- -6 Fig.

Fig. '7 is a detail sectional view on line 1--| Fig. 6, viewed from the right toward the left; and,

'Fig. 8 is a view, mainly in section, of a modified form of the fluid actuated ram cylinder construction on line 5-5 Fig. 6.

Fig. 9 is a detail sectional view on line 9-9 Fig. 4 viewed from the left toward the right, a portion of the rod connecting the upper and lower lever mechanisms being broken away to display the mechanism therebeyond;

Fig. 10 is a detail vertical sectional view on line Ill-ill Fig. 9;

Fig. 11 is a view of the sleeveand arms of the pump plunger actuating and restoring mechanism.

The elevating truck illustrated in the accompanying drawings has a main frame formed of parts electrically welded together to provide an integral construction. The main frame comprises essentially a pair of side frames each of which is formed of substantially outer and inner horizontal bars I and 2 (see Figs. 1 and 3) the rear ends of which are offset downwardly a distance substantially equal to the vertical depth of the side bars, preferably by welding, to, the under face of the side bar I, extensions 3, the front,

the load supporting means when in lowered posi-"- tion, as will hereinafter more fully appear. The

' inner side bar members 2 are similarly provided vwith downwardly offset extensions 5 and the rear ends of all the side bars are rigidly secured by welding to a rear connecting girder Ii. The rearaxle 1 of the main frame is journaled in the of the side frames, desirably are provided with antifriction bearings (not shown).

The front ends of the sideframes I and 2 desirably converge and are integrally connected by webs 9 and from such webs extend forwardly in parallelism. The front ends of the side bars I areconnected by welding to a head I0 and this union may also b'e strengthened by gusset plates I I which are welded to the side bars I and to the head I0. The head I0 has an integral forwardly extending bridge I2 of hollow rectangular vertical cross; section and is provided centrally of its length with 'a tubular bearing for a steering post, the lower end of said bearing having welded to it an enlarged circular disk I3 adapted. to be engaged by the fork of the steering mechanismand to permit antifriction bearings (not shown) to be interposed between the frame and the fork of the steering mechanism;- The head is also provided with a vertical arch II which desirablyis located slightly rearwardl'y of the bridge member I2 and is welded at its lower ends to thehead. The front ends of the side bar members 2 likewise are welded to flanges I5 extendingrearwardly from the head. By reason of this construction a is essential for trucks of heavyduty.

' The steering mechanism comprises' a hollow vertical steering post I8 which is mounted in the central bearing in the bridge I2 and is provided with a fork I] having at its lower end an very rigid integral main frame is provided which axle I8 upon which a pair of steering wheels I9.

are mounted. A split collar 20, which is clamped upon the upper end of the steering post, is provided with parallel forward extensions 2| in the upper 'end of which a shaft 22 forms the fulcrum for. a vertically swinging tongue. The swinging tongue comprises a handle member 23 which is per end of the collar member which is secured.

to the steering post.

- One of the features of the invention comprises 2 means. for normally maintaining the tongue in .within and axially of the hollow steering post.

vertical-position in order that the truck may oocupy a minimum amount of space and also .to provide a convenient support which may be grasped by the operator when operating the pedal actuated mechanical lifting mechanism which will hereinafter be described. In the present con struction the tongue is normally held in vertical position by a'coiled spring 28' which is located jack hereinafter described, the pump plunger of v 2,161,659 side bars I a sufficient distance to form rests for which is reciprocated by mechanism operable by vertical swinging movements of the tongue, the lifting jack mechanism also acting to sustain the load supporting means at any desired elevation,

with manually operable means for releasing the fluid pressure to permit the descent of the loadv supporting means.

The load supporting means comprises horizontal side frames having outer and inner side bars 28 and 29 complementary to the side bars l and 2 of the main frame, and spaced apart sufficiently to telescope over the'side bars I and -,2 when the load supporting means is in lowered position and to rest upon the upper surface of the rearward extensions 3 of the main side frames in such manner that the upper horizontal plane of the bars 28 and 29 of the load supporting means and the upper horizontal plane of the bars I and 2 of the side frames will substantially coin cide when the load supporting means is in lowered position and'resting upon the rearward extensions 3 of the side frames; By reason of this construction the load supporting means may be lowered to a minimum height to permit the truck readily to be introduced between a skid or article to be transported and by reason of the downwardly offset rear end portions of the main frame sumcient under-clearance is given to the truck to enable it to pass over sills, angularly disposed surfaces of a floor and ramp, and other converge toward each other at their front ends; and are connected by welding to a dash or standard I 32 having forwardly projecting flanges 33 and I! having shafts 35 forming pivots for front pairs of parallel links 36 the lower ends of which are pivoted upon shafts 31 in the main frame.

Theparallel links 38 desirably are each formed of a pair of flat triangular plates, as illustrated in Fig. 3, spaced apart by and welded to sleeves '38 and 38 which are Journaled respectively upon the shafts 35 and 31.. The rear end of the load supporting means is likewise connected to the main frame by parallel links 40 comprising parallel plates welded at their rear ends to sleeves II which are journaled at their upper ends upon shafts 42 in the load supporting means, said links 40 being pivotally mounted at their lower ends upon the rear axle I. l

In order to provide ample 'width of the side frames 28 and 29 of the-load supporting means ,to receive the, bearing shafts 42, the rear end portions of the side frames are provided with wider portions 43 extending downwardly and having beveled edges the forward edges of which are adapted to engage the complementary beveled surfaces upon the rear end of the extensions 3 and 5 of the and frame.

The mechanism for raising the load support ing means, as heretofore stated, comprises mechanically actuated means preferably operable by'a pedal for raisingthe load supporting means rapidly into engagement with the under surface of the skid or article to be lifted, and which also 'may be employed to raise the load support-. ing means when carrying a relatively light load .to a sufficient height to enable the load to be transported and selectively operable'fluid actuated means for raising the load supporting means step by step when a heavy load is to be lifted. Inasmuch as the ram of the fluid actuated lifting mechanism is connected to the load supporting means and adapted to be raised by the upward movement of the ram, either when actuated by fluid under pressure or by mechanical lifting mechanism, the fluid actuated mechanism will be first described.

The fluid actuated mechanism comprises a preferably hydraulic jack having a base block 44 which is rigidly secured to or formed integral with a downwardly extending bracket 45 which is journaled at its lowerend upon a shaft 46 mounted at its ends in the inner flanges I5 of the head to which the inner side bars 2 of the main frame are welded. By reason of this construction the lifting jack is pivotally mounted upon the main i'ramev in such manner that the ram may swing longitudinally of the. truck. The base block 44 has a central bore provided with screw threaded walls which receive the lower.

, end of a vertical ram cylinder 41 of the fluid plunger isscrew threaded and engaged by a fork actuated lifting mechanism (see Fig. 5).

The reservoir for the fluid comprises a cylinder 48 which is preferably concentric with the cylinder 41 and tightly tits at its lower end upon the outer surface of an annular boss 49 extending upwardly from the base block 44. The base block also is provided at'a suitable distance from the cylinder with another bore having a screw threaded wall which receives the screw threaded lower end of a vertical pump cylinder 50. A pump plunger 5| is reciprocably mounted in the pump cylinder 50 and is provided at its lower end with a screw threaded extension of smaller diameter presenting a shoulder and a piston packing 52 is clamped against said shoulder by suitable nuts upon the extension. The upper end of the pump cylinder 5| is provided with a suitable stuffing box 53 and the upper end of the pump or clevis 54 adapted to be attached to an actuating mechanism.

As illustrated in Figs. 5 and 6 the ram comprises a' ram shaft 55 which is reciprocably mounted in the cylinder 4'! and is provided at its lower end with an extension 56 of relatively small diameter and a piston head 51 and cup packing 58 are clamped against the shouldered end of the ram shaft by a suitable nut and washer. A can or head 59, which is screwedupon the upper end of the cylinder 41, is provided with a lateral extension or flange 59x which seats firmly upon the upper end of the reservoir cylinder 46. One or more recesses 60 in the cap 56 communicates with the space between the upper end of the cylinder 41 and the under face of the cap and provides a relief passage for discharging any fluid which may work up along the surface of the ram shaft into the reservoir. The upper end of the cap is countersunk and screw threaded to provide a stufflng box in which a suitable packing is forced tightly against the ram shaft by a nut 6|. Thecap 58 may be provided with one or more bores having screw threaded walls for the insertion of measuring rods 62 to determine the height of liquid in the reservoir when the ram shaft is in lowered position, the rod or ro s 62 being provided at their upper ends with enlarged screw threaded portions engaging the screw threads in the bore and also with a slotted head to receive the bit of a screw driver.

The upper end of the ram shaft 55 has secured to or integral with it a relatively large head 63, preferably of substantially rectangular cross section, which is bored horizontally and mounted upon a shaft 64, the ends of which are pivotally mounted in links 65, the other ends of which are pivotally mounted upon a horizontal shaft 66 which extends transversely across and is mounted in the upper portion of the arch l4 of the main frame. Links 61, which are also mounted at'their upper ends upon the shaft 64 which extends through the head of the ram, are pivotally connected at their lower ends to shafts 66 which are mounted in the front parallel links 66. By reason of this construction the lifting of the ram head 63 raises the rear ends of the forward parallel links 36 swinging them about their pivots 31, thereby moving the front end of the load supporting means upwardly and forwardly. At the same time the forward movement of the load supporting means swings the rear parallel links upwardly and forwardly so that the load sup porting means is raisedin substantial parallelism with the main frame.

Suitable mechanism is provided for actuating the pump to draw fluid from the reservoir and force it into the lower end of the cylinder, thereby to raise the ram shaft and ram. In view of the fact that the ram head 63 is guided in an arcuate path by the links 65 as it is raised and lowered, suitable mechanism is provided for reciprocating the pump plunger in an axial direction irrespective of the inclination of the'pump cylinder to the vertical. A sleeve 69 is welded to a rearwardly extending flange on the bracket 45 and has rotatably mounted in it a shaft 16 upon the ends of which is mounted a pump lever support comprising upwardly extending links H connected by a web 12. A shaft 13, which is mounted in bosses in the upper ends of the links H forms a fulcrum for a pump lever which comprises a sleeve 14 having integral therewith at one end forwardly projecting arms 15 and 16 and at the other end an integral forwardly projecting arm 11. The arm 15 extends between and is connected to the clevis 54 of the pump plunger by a pin 18. This pin extends also through the arm 16 and secures the same to a clevis 19 at the upper end of a rod 60 (see Fig. l), th'e'lower end of which is provided with a similar clevis 8| connected by a pin 62 to the intermediate portion of a lever 66 which is fulcrumed at its lower end upon the shaft I6 which extends through the sleeve 69 on the bracket 45. The forward end of the lever 83 is pivotally connected lever mechanism which is fulcrumed upon the shaft 66 which extends across the upper portion of the arch of the mainframe and is adapted to be actuated by vertical swinging movements of the tongue.

In order to permit the lifting of the ram and load supporting means selectively by mechanical lifting mechanism and by fluid operated lifting mechanism, the pump actuating lever, which is mounted upon the shaft 66, is formed in two sectionsadapted selectively to be connected toplates 81 are pivotally connected to the upper end of a strut 88 the axis of which is-substantially coaxial with the axis of the steering post portions of the rearwardly extending arms of the lever plates 81 and is provided with aforw'ardly extending handle II which extends through a.-

lon'gitudinal slot in a sleeve 82 which encloses said'gpin' and is welded at its ends to the, lever plates 81. The sleeve is provided with recesses 93 which serve to lock the pin in adjusted positions. when the pin- II is thrust to the r ht. as illustrated in Fig. 4, theend of the pin 88 extends into a'socket in'the arm 94 of the other section of the actuating lever 81, thus locking the sections of the actuating lever together. The arm 98 is integral with a sleeve 85 which also has a rearwardly extending arm 88, (see Fig.. 1)

which is provided adjacentits rear .end with a.

longitudinal slot. A slide .81, which is mounted upon the rearwardly extending lever arm 86, is pivotally connected to the clevis 86 by a pin 88 which extends through the forked arms of. the

slide, the slot in the lever arm 86, and the arms of the clevis 86. An adjusting screw, which is rotatablysecured in a boss Ill extending upwardly from the sleeve 95, is provided with a knurled head III by means of which the screw may be rotated to move the slide 81 forwardly or backwardly, thereby varying the eifective length of leverage -of the pump actuating lever which is transmitted through the pump link or rod 85 to the lever 83 through which'recipro- Bitcationis imparted to the pump plunger. reason of this construction the eifective force applied to the pump plunger and itslengthof stroke may be adjusted in correlation to 'the weight of the load upon the loadsupporting means. Therefore, by adjusting the slide 81 may be disengaged from the rearwardl'y extending leverarm 84, thereby detaching'the mechanism which is operated bythe vertical reciprocating movements of the tongue from the fluid actuating mechanism, so that the ram head'and ram may be lifted independently of the fluid actuated lifting mechanism.

Desirably means are provided for aiding in raising the pump plunger when the swinging tongue is raised after having been depressed. In the preferred construction illustrated herein a pump return spiral spring I02, which is seated at its lower end upon an'extension Ill of the bracket-A5 which supports the base 44 of the fluid actuating mechanism and at its .upper end engages the lower end of a clevis I upon a downwardly extending guide rod I05 which projects through the bracket extension I. The clevis IN is pivotally connected to the forwardly extending arm TI of the sleeve ll, other arms II and 16 of which are pivotally" connected respectively to the pump plunger BI and to the rod 80 through which power is transmitted to the pump plunger from the lever 83 (see Figs. 1 and plunger and to restore the lever mechanisms and tongue to upraised position.

Suitable means are provided for transmittingfluid pressure upon the actuation of the pump plunger to the lower portion of the ram cylinder, thereby to raise the ram and load supporting means. ,In the. preferred constructions illustrated herein the base block 44 is provided with suitable conduits through which the fluid is drawn from the reservoir into the pump upon the upward movement of the plunger and forced from the pump into the lower end of the cylinder .upon downward movement of the pump plunger. These conduits are particularly shown in Figs. 5, 6, and 7, in which the base block is provided with an arcuate recess I06 which communicates with one end of a bore llll which communicates with a vertical bore I08 having a countersunk portion I88. The upper end of the bore I88 communicates with a transverse bore Ill leading to a vertical bore III which com-' municates. with the lower end of the pump cylinder. The countersink I08 of the bore I88 provides a valve seat for a' ball valve H2 and the upper countersunk portion of the bore "I8 is provided with a screw threaded plug H3 theend of which is located slightly above the ball 80 as topermit the ball to be raised when fluidis drawn from the reservoir through the bores I81, I88, and III by the upward orsuction movement of the pump plunger. Upon discontinuance of the upward movement of the plunger the .ball II2 will drop to its seat and prevent retrograde movement of the fluid when the pump plunger is. forced downwardly. I.'; .The bore .III., which communicates with the lower end of the pump, also communicates with a bore Ill which is plugged at its outer end and p which communicates intermediate of its ends with a short vertical bore I II which in turn communicates with a bore or. conduit I I6 leading to a vertical bore III extending downwardly from the bottom of the ram cylinder. The vertical bore H5 is countersunk to provide a seat for a ball valve III which is normally held seated by aspring II! the upper end of which is engaged-by a screw threaded-plug in the enlarged countersink of the bore Ill. Upon depression of the pump plunger the fluid is forced through the conduits III, III, II, and Ill, into the ram Q cylinder, thereby raising the ram. When the fluid is forced in this direction the ball valve I I8 reservoir and force it under pressure into the ramcylinder, thereby raising the ram and the load supporting means.

Upward movement of the ram piston is limited by providing a port III in the wall of the cylinder at a predeterminedzheight to permit escape of fluid from the ram cylinder to the reservoir when the piston at the lower end of the raised to a suillcient height. c

In order .to prevent clogging of the conduits ram shaft is for the fluid an annular screen I2I is located in the recess formed between the ram cylinder and the flange 88 and a similar screen I22 is also located in a countersinkln the base below the end of theram cylinder.

Fluid may be introduced into the reservoir prises manually controlled means for releasing the fluid pressure in the pump cylinder, to permit the descent of the loadsupporting means, of I such construction that the descent of the load supporting means can be accurately controlled and which requires continuous manual control during the descent of the load supporting means, so that-unless the operator continuously maintains control of -such releasing mechanism the escape of fluid under pressure from the cylinder will be instantly stopped, thereby preventing such descent of the load supporting means as would be likely to create shock which might damage the articles being transported or the truck itself.

The means for releasing fluid pressure in the ram cylinder, which is shown particularly in Figs. 5 and 6 of the drawings, comprises a conduit I22 "which communicates with the lower end of the ram cylinder through the screen I 22 and is plugged at its outer end, but communicates intermediate of its ends with a vertical port I24 leading to a conduit I25 having an outer plugged end and the inner end of which communicates with a vertical bore I 26 the upper end of which communicates through the screen I2I with the reservoir. The base block 44 is provided with a vertical bore in axial alinement with the port I24 to receive a valve stem I21 the lower end of which is reduced in diameter and tapered to provide a valve fltting a complementary valve seat at the upper end of the port I24. The valve stem I21 has an enlarged screw threaded portion I22 which engages complementary internal threads in a nut I 29 which is externally threaded to engage threads in the wall of the countersink. The countersink is of suilicient depth to receive asuitable packing I22 thereby providing a stufling box for the valve stem which will prevent escape of the liquid under pressure. which is forced through the conduits I22 and I2! from the ram cylinder intothe reservoir.

Desirably the means for controlling the outlet 1 valve is mounted at a convenient place upon the upper end of the arch I4 and in view of the fact that the fluid actuated unit and ram cylinder are pivotally mounted upon the base to swing forwardly and rearwardly, means are provided for actuating the outlet valve which will not be interfered withby such swinging. movement of the liower'unit.

In the preferred construction illustrated, (see Fig. 4) the upper end of the valve stem I21, I22,

1| chooseto-position it.

is provided with a clevis In which is pivotally connected to acomplementary member I22 which is fixedly secured to a rod I22 extending upwardly through the arch I4 and has secured to its upper end a preferably cylindrical head I24 provided with an operating handle. For convenience of manipulation the upper end of the head I24is diametrically slotted and the ball-shaped endof a lever I2! is so mounted in the slot that it canbe moved from-vertical position either to the right ,or left into horizontal position. -A coiled spring I22 seated at its lower end upon the upper 79 end of the rod I22 and has at its upper end a suit ablebearing e s ses the flattened face upon the ball adapted toholdthe lever in vertical position. but also serves to hold the lever in either of the horizontal positions in which the operator may In orderto insure the maintenance of the valve I21 in closed position and to close, it if the operator should release the operating lever I25, a

coiled spring I21 which surrounds the rod I25 is secured at one end to the arch I4 and atits other end to a collar I28 which is fixedly secured upon the rodl22,the tension upon the spring I21 being such as to tend to rotate the rod I22 in a direction to close the valve. H

When it is desired to release the fluid under pressure from the ram cylinder the handle I2! is turned in the direction to' unscrew the screw threaded portion I22 of the valve stem from the nut I22, thereby gradually raising the valve and permitting the fluid to flow through the conduit I22, the port I24 and conduit I 22 into the reservoir. If the operator should release the handle at any time the spring I21 will rotate the valve stem in a direction to restore the valve to seated position, thereby preventing any uncontrolled descent of the load supporting means.

In order to permit fluid to flow from the reservoir into -the ram cylinder when the ram is raised by mechanical means hereinafter described, the base block 44 is provided with a conduit comprising a vertical bore I22 leading downwardly from the reservoir and communicating with a horizontal bore I40 which is plugged at its outer end and which at its inner end communicates .with a vertical bore I4I in the bottom or the ram cylinder. The. upper'portion of the bore I is countersunk to provide a seat for a ball valve I42. When therefore the ram cylinder is raised mechanically the ball will be unseated to permit fluid to flow from the reservoir into the ram cylthe ram cylinder beneath the plunger when thus raised mechanically. Upon cessation of the upward movement of the ramthe ball will immediately seat thereby preventing the return of fluid from the ram cylinder to the reservoir. By reason of this construction the fluid in the ram cylinder will prevent downward movement of the ram and the load supp rting means will-be rejtalned inraisedpositionunlessanduntilthefluid is released from the ram cylinder in the manner herein described.

-A preferred and simplified form of ram cylinder and ram shaft construction is'illustrated in Fig. 8 of the drawings. In this construction the ram shaft 52 is carefully surfaced to fit tightly but slidably in the ram cylinder 41, thereby obviating the necessity of a piston head and packing at the lower end of the ram shaft. The upper end ofthe cylinder 41 is screw threaded and has 1 mounted upon it a cylindrical sleeve I42 having .a central recess provided with an internal screw threaded wall complementary to the screw threads upon the upper end of the cylinder and is provided with a web I44 which fits upon the ramshaftll. 'I'hesleeveisboredfromits upper end to provide a'chamber I4l adapted to receive a suitable chevron packing formed of a plurality of annular packing rings I42 V-shsped in cross tion and superimposed upon eachother upon ular ring-I41 having a V-shaped upper surface complementary to but of somewhat wider angle than those of the y-shaped packing rings. The upper end of the sleeve I43 is counterbored and internally screw threaded to receive an externally threaded nut I48 having a V-shaped un-e der surface adapted to engage the uppermost of the V-shaped rings of the chevron packing. The upper end portion of the sleeve I43 is externally screw threaded and is engaged by an internally screw threaded downwardly extending flange on a cap I49 having a peripheral flange which engages the upper end of the cylindrical reservoir wall 48 and serves to clamp the-reservoir wall firmly upon the shoulder on the base block surrounding the annularboss 49 of the base block. The upper portion of the cap iscounterbored and internally screw threaded to receive a nut I50 which clamps a packing tightly upon the ram shaft, thereby providing a stuihng box construction eifective to de the ram shaft and to fluid.

In order to limit the upward movement of the ram shaft to a position safely within the ram cylinder and also to determine the upward movement .of the load supporting means, means are provided for releasing fluid under pressure from the ram cylinder when the ram shaft has reached a predetermined height. In the particular construction illustrated the nut I48 is provided intermediate of its length with an annular groove I5I having radial outlets which communicate with vertical bores I52 leading to a space between the cap and the nut I46 which communicates with radial bores I53 in the cap through which the fluid may be discharged into the reservoir. The ram shaft 55 is provided with a vertical bore.

prevent the escape of I54 extending upwardly from its lower end to a predetermined height with a lateral port I55 extending therefrom through the l of the ram and adapted when registering with the groove I5I to discharge fluid under pressure into it. While.

the port I55 registered with the groove I5I fluid passes from the ram cylinder through it and the vertical bores I52 in the nut into the space between the nut and the lower face of the cap and is discharged through the outlet I53 into the reservoir. Upon cessation of the reciprocation of the pump cylinder the ram shaft will lower slightly untilthe port I55 is out of registry with the groove I5I and the ram shaft and ram will then be sustained in upraised position by the fluid which is trapped in the cylinder beneath the-ram shaft.

The selectively operable mechanical lifting means As heretofore stated, one of the principal objects of the present invention is to provide 5 mechanically operated means for rapidly raising theloadsupporting means into engagement with the under face of the skid, where heavy loads are to be lifted, with fluid actuated means there after operable to apply greater power to lift the load supporting means step by step.

In the preferred embodiment of the invention illustrated herein the mechanically actuated lifting mechanism comprises a lever preferably in the form of a pedal I56 fixedly secured to a sleeve I51 which is mounted upona stud shaft I58 extending through and mounted in the head -I and the flange I5forming one side of the main frame. The sleeve I 51 has anintegral rearwardly extending arm I59 the rear end of which extends ly and slidably mounted in the tubular thrust member BI, is provided with an enlarged head I64 which is pivotally mounted upon a stud I65 which extends outwardly from a'link 61 which connects the head 63 of'the ram tothe front parallel links 36 connecting the load supporting means to the frame. The rod I63, which extends into the tubular thrust member I 6I, is of such length that when the foot lever is in raised position and the load supporting means in lowered position it will engage the head I60 or other suitable abutment at the lowerend of the tube, so that when the lever is depressed the tube member and rod will be in effect a continuous thrust member which when the pedal is depressed will raise the link 61 and the head 63 of the ram and will pull the front parallel links 36 upwardly and forwardly thereby directly raising the load supporting means. As the load supporting means is thus mechanically raised fluid will flow from the reservoir through the conduits I39, I40, and HI into the cylinder and upon cessation of the upward movement of the ram shaft the ball valve I42 will close and by trapping the fluid in the ram cylinder will sustain the load supporting means in its raised .position. A coiled spring I66, which is interposed between the head I64 of the thrust rod I63 and the-upper end of the tube I 6|, exerts a downward pressure upon the rearwardly extending arm I59 of the pedal actuated lever and tends to hold the pedal I56 in vertical position illustrated in Fig. 1 and to return it to that position after it has been depressed v and released. The pedal lever I56 may be-prevented from passing beyond a predetermined substantially vertical position by a pin I61 projecting from the side frame into thepath of the pedal arm.

' The telescoping thrust members comprising the tube and rod above described also provide in ef- .-fect an extensible thrust member adapted to permit further raising of the load supporting means by the fluid operated Jack without interference with the actuation of the fluid actu-- ated mechanism.

In order to facilitate convenient manipulation ofthe fluid actuated mechanism when heavy loads of different weight are to be lifted, the

tongue is provided with an adjustable extension by means of which the leverage applied by the .operator with substantially the same exertion of force may be varied. A preferred construction is illustrated in Fig. 2 in which a cylindrical bar I68 is slidably mounted in the end portion of the tubular tongue 23. The bar I68 is provided with a longitudinally extending groove I69 having at intervals suitable depressions or sockets I10 lengthwise of the tubular tongue, it is only necessary to back 01! the screw I13, slide the bar I68 longitudinally until the selected socket I10 is in alinement with the screw HI, and then rotate the screw in a direction to seat it in the selected socket so that it will firmly hold the bar in adiusted position. The bar I68 is provided at its outer end with a suitable fitting I14 having a transverse tubular handle member I15, of convenient size to be grasped by the operator, tending through it. I

If desired a sheet metal cover or casing (not shown) may be provided to enclose the fluid accealed and protected from dust and injury.

In'the operation ofthe'truck the load supporting means may be lowered by manipulation of the'handie I35 to open the outlet valve, thereby permitting fluid to flow from 'the ram cylinder into the reservoir until the load supporting means has reached its lowermost limit and the uppersurface thereof is flush with the upper surface of the main frame. When in such lowered position the truck can be readily backed beneath the skid weighted with the articles to be transported, or beneath an article whose base is of sumcient height to permit the introduction of the truck therebeneath, After the truck has been positioned beneath the skid or other article to be transported the foot pedal lever I56 is depressed by the foot of the operator thereby rotating the sleeve I51 to which it is rigidly connected so that the rearwardly extending arm I59 of the sleeve will raise the tubular thrust member, thereby compressing the spring I66 which surrounds the thrust rod I63 until the coils of the spring engage each other, or until the lower end of the rod I63 engages the head I60 of the tubular thrust member IIiI., Such depression of the pedal lever causes the thrust members to raise the link 81 and the ram head and the load supporting means to which the respective ends of the link 61 are connected. A single depression of'the foot pedal therefore raises the load supporting means quickly until the latter engagesthe floor of the skid.

As the ram head is thus raised by the mechanical lifting mechanism operated by the foot lever, liquid flowsfreely from the reservoir to the ram of the pressure upon it, forces the tubular section I6I of the thrust member downwardly, thereby.

, restoring the foot lever to its normal. upra'ised position as shown in Fig. 1.

If it is desired to lift the load supporting means .by the foot lever when the tongue is in upright position, as shown in Fig; 1, the handle SI of the pin 80 is moved to the left, Figs. 4 and 10, to release the pin 90 from engagement with-the arm 94 of the right hand section of the actuating lever. If the tongue is in lowered position such disconnection is not necessary as the lifting of the ram will swing the tongue upwardly.

In order to lift the load supporting means and the skid or other'article engaged by it, the tongue is rocked toa position in which the pin 90 can beinserted into the socket in the arm 94 of the actuating lever section. The pin 90 is then moved to the right, Figs. 4 and 10, into engagement with the socket, thus locking the sections of the actu-' ating lever together. The tongue is then raised the operator. the handle I" the spring I" will immediately and lowered vertically to actuate the pump and thereby force-fluid into the ram cylinder.

-During the downward swinging movement of the tongue the tongue extension 25 raises the strut 89 vertically in the direction of the axis of the steering post irrespective of the steering position of the tongue. The upward movement of the strut 89 rocks the actuating lever, the for-- wardly extending arms 81 and 94 of which are now connected by the pin 90, causing the rearwardly extending adjustable arm 86 to depress the link 85, thereby swinging the lever 83, to which the lower end of the link 85 is connected, downwardly about its fulcrum III.

p The link 80, which is connected to the .lever 83 intermediate of the connection of the link 85 and the fulcrum I of the lever 83, is thereby drawn downwardly and as the upper end of the link 80 is connected to the forwardly extending arm I8 of the sleeve II the arm I6 is swung downwardly. Inasmuch as the sleeve 'Ifhas also forwardly extending arms I and 11 they also are swung downwardly. As'the arm I5 is pivotally connected to the pump plunger the pump plunger is forced downwardly thereby forcing the fluid from the reservoir into the ram cylinder and raising the ram.

The other arm 11 of the sleeve I4 is connected to a guide rod I! which is encircled by the spring I02 and the downward movement of the arm Iii thereby compresses the spring I02, thus storing up power which when downward pressure on the tongue is released tends to restore the lever mechanisms and thetongue to upraised position, thus relieving the operator partially 'at least of the effort of raising the tongue. Repeated vertical swinging movements of the tongue will therefore pump fluid into the ram cylinder thereby raising the ram and load supporting means step by step.

By reason of the construction above described it is obvious that the mechanically actuated lift.- lng mechanism is supplementary to the fluid actuated "mechanism and is not alternative there- I with as in prior elevating truck constructions and its destination. When it is desired to lower the skid or other article the operator will grasp the handle I I! and rotate it in a direction to raise the outlet valve from its seat, thereby permitting oil to flow from the ram cylinder into the reservoir at a rate which is controlled at all times by If at any time the operator releases act upon the rod I to rotate the valve stem in a direction to close the valve promptly, thereby preventing further descent of the load;

an illustrative character and is not restrictive,

and that various changes may be made in form,

construction and arrangement of. parts within able load supporting meansand means for raise @mg the load supporting means comprising aflu'id ,operated-jack havingla reservoir, a. cylinder, 9. -'ram-conne'cted to said load supporting means- 1 andmeans for forcing fluid under pressure from said reservoir .to said cylinder tojraise'the load supporting means step by step, and an auxiliary I i-mechanically operable lifting mechanism, selectively operable means for. actuating saidme'chanical lifting mechanism 'to raise the load supporting means, means forja'dmittin'g fluid from said reservoir to said cylinder upon the raising of said load supportingmeans by said mechanically operablamechanism, andmeans-for releasing the -.fluid from said cylinder topermit the load supporting means to descend.

2. An elevating truck having upwardly movable load supporting means andlmeans for rais ing said load supporting means comprising a fluid operable jack having acylinder and a ram connected to said load supporting means, actuating. 'means for forcing fluid under pressure into said cylinder to cause said ramto raise said load supporting means, and auxiliary mechanically actuated lifting means engaging said ram and operable -to raise said ram and said load supporting means in advance of the actuation of said fluid actuating means.

3. An elevating able load supporting meansand means for raising said load supporting means comprising a fluid operable jack having a cylinder and a ram connected to said load supporting means, means for forcing fluid under pressure into said cylinder. to cause said ram to raise said load supporting,

means, mechanically actuated means operable to raise said load supporting means in advance of the actuation vof said fluid actuated means, and means operable during the raising of said 'load supporting'means by the mechanically actuated means to admit fluidto said cylinder and retain it therein, thereby to prevent the lowering of 'said load supporting means upon release of said mechanically actuated lifting means, and manually controlled means for releasing fluid from said cylinder to permit thelowering of said load supporting means. v

4. An elevating truck having, s tee ring mechanism including a tongue mounte'd'to swing vertically and upwardly movable load supporting means comprising mechanically actuated means operable toraise'said load supporting means rapidly into engagement with the device to be lifted and fluid actuated lifting means operable by vertical swinging movement of the tongue .to raise said load supporting means stepv by step, and means actuated by the mechanicallyactuated lifting means to cause the fluid of the fluid actuated lifting means to prevent descent of the load supporting means when raised by said mechanically actuated. lifting means. V a

5. An elevating truckhaving steering mecha-. I

nism including a tongue mounted to swing vertically and upwardly movable-load supporting.

means comprising mechanically actuated lifting means operable by a single stroke'of' a pedal lever toraise the load supporting means'to a predetermined height and fluid actuated lifting means operable by vertical swinging movements of said tongue thereafter to raise said load supporting means-step by step and means actuated by the mechanically actuated lifting means to cause the 'fluid of the fluid actuated lifting means to prevent descent of the loadsupporting means when raised by .said mechanically actuated lifting 1s I means.

truck having upwardly mov-- f 6. An elevating truck'having steeringmechanism including a tongue mounted to swing vertically and upwardly movablev load supporting' means, meansfor raisingjsaid load supporting means comprising a fluid operated jack having a' substantially vertical cylinder and a ram, means connecting the upper end of said ramto said load supporting means, mechanical leveractuated means for preliminarily raising said ram and load supporting means to cause the load supporting means tojengage the device to be lifted, means operable to admit and retain fluid in said cylinder as said ram is raised by said 1 ,me'chanically actuated means, and means'operable by vertical swinging movements of the tongue to force fluid under pressure 'into said cylinder thereafter to raisesaid load supporting means step by step, and manually controlled means for releasing fluid from said cylinder to permit descent of said loadsupporting means.

7. An elevating truck having a' wheel-supported main frameand an upwardly movable load sup porting means, means 'for raising said load sup.-

porting means comprising-a fluid operated jack mounted on said main frame having a substantially vertical cylinder and ram, means connecting the upper end of said rain to said load supporting means, a lever fulcrummed on said main frame having an extensible connection to said ram operable to raise saidram and said'load means comprising a fluid operated jack mounted on said main frame having a substantially vertical cylinder and ram, means connecting the upper end of said ram to'said'load supporting means, a lever fulcrummed on said main frame having an extensible'connection to said ram operable to. raise said ram "and load, supporting means to a predetermined heigh and thereafter means for admitting fluidto said cylinder as the ram is raised, and means operable byvertical swinging movements of" the tongue to force fluid under pressure into said cylinder further to raise said ram and load supporting means step by step.-

9. An elevating truck having a wheel-supported main frame provided with steering me'chanism including a tongue mounted to swing vertically and upwardly movable load supporting means,'means-forfraising said load supporting means comprising a fluid operated'jack-mounted on said main frame having asu'bstantially vertical cylinder and ram, means connecting the upper'end of said ram to said load supporting "means, a foot lever fulcrumed on said main frame, telescoping thrust members connecting .60 to permit further upward movement of said ram,

said foot lever to said ram operable by-asinSlQ depression of said foot lever to raise said-ram and load supporting means. to a predetermined; height and thereafter to permit further upward movement of said ram, means for admitting fluid to said cylinder as the .ram is raised, and means operable byvertical' swinging movements of said tongue to force-fluid under pressure into said porting means step by step. a

10. An elevating truck having a wheel-supported main frame provided with steering mechanism including a tongue mounted to swing vertically' and upwardly movable load supporting means, means for raising said load supporting means comprising a fluid operated jack mounted on said main frame having 'a substantially vertical cylinder and ram, means connecting the upper end of said ram to said load supporting means, a foot lever fulcrumed on said main frame, telescoping thrust members connecting said foot lever to said ram operable by a single depression of said foot lever to raise said ram and load supporting 'means to a predetermined height and thereafter to permit further upward movement of said ram, means for admitting fluid to said cylinder to fill the same as the ram is raised, means operable by vertical swinging movements of said tongue to force fluid under pressure into said cylinder further to raise said ram and load supporting means step by step, and resilient means interposed between said telescoping thrust members operable to raise said foot lever to substantially vertical position upon release of the force applied thereto.

11. An elevating truck having a wheel-supported main frame with a rigid upwardly extending arch adjacent its front end and provided with steering mechanism including a tongue mounted to swing vertically and movable laterally to any steering position, and upwardly movable load supporting means, a fluid operated jack mounted on-said main frame comprising a vertical cylinder having a rainv connected to said lead supporting means and a pump, means for actuating the pump plunger comprising a lever fulcrumed in the arch of saidframe and having its forward arm projecting across the vertical axis of the steering mechanism, means operable by vertical swinging movements of the tongue when in any steering position to actuate said lever, and means operable by the rearward arm of said lever for actuating the pump plunger, and means for varyingthe effective leverage of said plunger actuating lever. a Y

12. An elevating truck having a wheel-supported main frame with a rigid upwardly extending arch adjacent its front end and provided with steering mechanism including a tongue mounted to swing vertically and movable laterally to any.

steering position, and upwardly movable load supporting means, a fluid operated jack mounted on said main frame comprising a vertical cylinder having a ram connected to said load supporting means and a pump, means for actuating the pump plunger comprising a lever fulcrumed in the arch of said frame and having a forward arm projecting across the vertical axis of the steering mechanism and an arm projecting rearwardly from the'fulcrum of said lever, means operable by vertical swinging movements of the tongue to actuate said lever, means operable by the rearward arm of said lever for actuating the pump plunger, and means for adjusting the effective length of the rearwardly extending arm of said lever, whereby the force applied to the pump plunger and the length of stroke of said plunger may be varied.

13. An elevating truck having a wheel-supported main frame with a rigid upwardly extending arch adjacent its front end and provided with steering mechanism including a tongue mounted to swing vertically, and upwardly movcylinder further to raise said ram and load supable load supporting means, a fluid operated jack mounted on said main frame comprising a vertical cylinder having a ram connected to said load supporting means and a pump, a horizontal shaft mounted in the upper portion of said arch, a. pump actuating lever pivotally mounted upon said shaft having a slotted rearwardly extending arm and a forwardly extending arm projecting across the vertical axis of the steering mechanism, means operable by vertical swinging movements of the tongue to actuate said lever, a slide adjustably mounted upon said slotted rearwardly extending arm, means including a screw for adjusting the position of said slide, a link pivotally connected to said slide, and means operable by said link to actuate said plunger, whereby the effective force applied to the pump plunger and the length of stroke of the plunger may be varied by adjustment of said slide upon said rearwardly.

projecting arm. I

14. An elevating truck having a wheel-supported main frame with a rigid upwardly extending arch adjacent its front end and provided with steering mechanism including a tongue mounted to swing vertically, and upwardly movable load supporting means, a fluid operated jack mounted on said main frame comprising a vertical cylinder having a ram connected to said load supporting means and a pump, a horizontal shaft mounted in the upper portion of said arch, a pump actuating lever formed in sections each pivotally mounted upon said shaft, one of said sections having a forward arm projecting across the vertical axis of the steering mechanism, means operable by vertical swinging movements of the tongue to actuate said arm, the other arm of said lever extending rearwardly and having means connected thereto for actuating the pump plunger, releasable means for connecting the arms of said pump actuating lever together,

a foot lever pivotally mounted upon said frame,. and extensible means connecting said foot lever to said ram operable by a single depression of said foot lever to raise said ram and load supporting means to a predetermined height and means operable during the raising of said ram by said foot lever mechanism to admit fluid to said ram cylinder to fill the same, whereby upon release of the foot lever actuated mechanism the load supporting means will be retained in elevated position by the fluid in the ram cylinder. 15. An elevating truck comprising a main frame having a head, steering mechanism mounted in said head, side frames rigid with said head extending horizontally rearwardly therefrom and having rear end portions offset downwardly therefrom a distance substantially equal to the vertical depth thereof and having laterally extending upper surfaces to provide supports for said load supporting means, wheels having their axles journaled in said downwardly offset-portions, thereby providing ample under-clearance for the truck, upwardly movable load supporting means having side frames substantially the same vertical depth as the rearwardly extending main side frames, and positioned to telescope over said main side frames and'when lowered to rest upon said supporting surfaces of th offset portions of the main frame so that the horizontal planes of the upper edges of the main side frames and those of the load supporting means will substantially coincide when the load supporting means is in lowered position.

16. An elevating truck comprising a main frame having a head, steering mechanism mounted in said head, side frames rigid with said head extending horizontally rearwardly therefrom and having rear end portions offset downwardlyv therefrom a distance substantially equal to the vertical depth thereof and of such greater width than the side frames as to extend outwardly' beyond the outer vertical planes of the side frame members and form supports for the load supporting means when in lowered position,

wheels having their axles mounted in said downwardly offset portions, upwardly movable load supporting means having side frames of substantially the same vertical depth as the rearwardly extending main side frames adapted when in lowered position to telescope over said main side frames and rest upon the supports of the offset rear end portions thereof, so that the horizontal nected to the front end of said load supporting 17. An elevating truck having .a wheel-sup-.

ported main frame with a rigid upwardly extending arch adjacent its front end and provided with steering mechanism including a tongue mounted to swing vertically and having an extension projecting over the vertical axis of the steering post, upwardly movable load supporting means, a fluid operated jack mounted on the main frame comprising a vertical cylinder having a ram connectedto said load supporting means and a pump, means for actuating the pump plunger comprising a lever fulcrumed in the arch of said frame and having its forward end projecting across the vertical axis of the steering mechanism and-having a strut extending in the direction of the axis of the steering post connecting the same to said tongue extension, means operable by said pump actuating lever to reciprocate said pump plunger, and a spring connected to said tongue extension operable normally to hold said tongue in vertical position.

18. An elevating truck having a' wheel-supported main frame with a rigid upwardly extending arch adjacent its front end and having a head,

steering mechanism having avertical tubular steering post mounted in said head, a vertically swinging tongue fulcrumed upon said steering post and having an extension. projecting across the vertical axis of the steering post, a spring conto said load supporting means operable by vertical swinging movement of said tongue to force fluid under pressure into said ram cylinder thereby to raise said load supporting means, and auxiliary pedal actuated mechanical means operable preliminarily to raise said load supporting means while the tongue is retained in vertical position and means for admitting fluid into said ram cylinder to fill-the same as the load supporting means is raised by said pedal actuated means.

19. An elevating 'truck comprising a wheel-supported main frame with anarch adjacent its front end and provided with steering mechanism 'having a tongue mounted to swing vertically, load supporting means connected to said main frame by front and rear pairs of parallel links, a fluid operated jack unit pivotally mounted at its lower end on-said main frame and comprising a pump and a vertical cylinder and ram, a horizontal shaft mounted in the head of said ram, lifting links connecting said ram shaft to said front parallel links, a horizontal shaft in the upper portion of said arch, links pivotally mounted at their front ends on said arch shaft and at their rear ends on said horizontal ram shaft operable to insure substantially vertical movement of said ram, and means operable by vertical swinging movements of said tongue to actuate the pump plunger and thereby force fluid under pressure into said cylinder to raise said ram and load supporting means. 20. An elevating truck having a wheel-supported main frame having steering mechanism including a vertically swinging tongue and load supporting means movable upwardly relatively thereto, means for raising said load supporting means comprising a fluid operated lifting jack unit having a base block pivotally mounted on said main frame, a cylinder and a pump extending vertically upwardly from said base, a ram shaft slidably fitting said cylinder having a ram connected to said load supporting means, a tubular reservoir enclosing said cylinder having at its upper end a head closing the upper end of said reservoir and provided with .a stuffing box tightly embracing said ram shaft, said base block having conduits provided with suitable check valves for conducting fluid from said reservoir to said pump and upon actuation of 'said pump to conduct fluid under pressure from the pump to said cylinder to raise said ram, means operable by-vertical swinging movements of said tongue to actdate the pump plunger, pedal actuated means mechanically connected to said ram operable by a single depression of said pedal to raise said ram and load supporting means, and a valved conduit in said base communicating with said reservoir and cylinder operable to permit fluid to flow from said reservoir into said cylinder when the ram is raised by said pedal actuated means.

21. An elevating truck having a wheel-supported main frame having steering mechanism including a vertically swinging tongue and load supporting means movable upwardly relatively thereto, means for raising said lead supporting means comprising a fluidoperated lifting jack unit having a base block pivotally mounted on, said main frame, a cylinder and a pump extending vertically upwardly from saidbase, a ram Yshaft slidably fitting said cylinder, a tubular reservoir enclosing said cylinder having at its upper end, a head closing the upper end of said reservoir having a'part detachably secured to said cylinder andprovided with a stuffing box 'tightly embracing said ram shaft, said base block having conduits provided 'with suitable check valves for conducting fluid from said reservoir supporting mieans movable upwardly relatively to said main frame, means for raising said load supporting means comprising a fluid operated jack pivotally mounted on said main frame having a reservoir, a pump and a vertical cylinder, a ram reciprocably mounted in said cylinder, means' pivotally connected to said ram and to said load supporting means to permit relative longitudinal movement between said load supporting means and said frame, means for actuating the plunger of said pump, suitably valved conduits for conducting fluid from said reservoir to said pump and for conducting fluid under pressure from said pump to said cylinder to raise said ram and load supporting means, an outlet conduit leading from said cylinder to said reservoir, a valve for said conduit having a screw threaded stem operable when rotated in one direction to close said conduit and when rotated in the opposite direction gradually to open said conduit, a rod mounted in said arch having a flexible connection to said valve stem, a spring engaging said arch and said rod acting normally to rotate said rod in a "direction to cause the valve to close said outlet conduit, and a handle on said rod for rotating the valve stem against the force of said spring in a direction to open said conduit.

FREDERICK J. SHEPARD, J R. NATHANIEL WARSHAW. 

